Tooth sensitivity (dentinal hypersensitivity) is a painful response to physical, chemical or thermal stimuli and can affect one in seven dentate adults. Although the clinical features of dentinal hypersensitivity are well described the physiological mechanisms are not as well understood. The most widely accepted theory suggests that dentinal tubules act as channels that enable the different stimuli to reach the pulp and elicit pain. Compounds used in treating hypersensitive dentine include formalin and silver nitrate, glycerine, strontium chloride, dicalcium phosphate, potassium nitrate, sodium fluoride, sodium citrate, calcium hydroxide, resins, potassium oxalate stannous fluoride and cyanoacrylate. It is believed that most of the above agents reduce dentinal hypersensitivity either by mineralizing, or precipitating at, the entrance of the dentinal tubules thereby blocking stimuli.